CEL # po141, po171 & po174

[Glenn Lyle]

Many thanks to you who have been assisting or can finally diagnose this one.



I had my 01 (job 1) scanned about a week ago with 3 codes (unknown numbers) but was told it was 3 of the 02 sensors (2 before & 1 after the cat) that needed replacing.



Today I got it scanned. was given 6 codes- 2 of them po141, 2 of them po171 and 2 of them po174. This time, I'm told the 02 sensors (1 before & 1 after cat.) are bad, only I need two of them instead of 3.



What gives? ANY suggestions on this will be greatly appreciated. How many O2 sensors are there on a 01, job 1?



Thanx.

 

[TRACket Paul]

Change the 1st sensor.

 

[Kevin Palmer]

I know we have gone over this with you but don't quit looking yet. I am sure you will find a defective hose or intake gasket. This creates the system to run lean ans the O2 senses this. It then trips the CEL to let you know you have a problem.



It is coming back as defective or out of range O2 sensors simply because it is out of range. But I would bet lots of money it is out of range as a result of a defective hose or gasket.



Have you done the spraying trick I mentioned????

 

[Glenn Lyle]

tried it, but didn't have any luck. Not sure I hit all the vacumn hoses. Should I spray the air "hose" from the mas also? And, how many 02 sensors are there on an 01/job 1?



This is about to drive me insane. BTW, what is the plastic piece that runs off air "hose" just past the mas and goes to the rear/top of the motor to what I believe is the iac motor (it's under the plastic cover with 4.0 on it).



IF i replace the 02 sensors, but it has a leak, it'll still fail inspection right?!

 

[Tom Schindler]

If you replace something that is not bed, the problem will not be fixed. If it does not get fixed, you will fail inspection. The Trac should have three O2 sonsors. One for each bank, and one after the catalytic converter. The two "upstream" sensors are to monitor the engine. The "downstream" sensor is there to monitor the converter to make sure they are working properly.



A trick old mechanics do is they use a propane tortch to find a vacuum leak. The turn the gas on, but do not light it. They let the gas slowly seep out of the tortch and start checking vacuum hoses, while the engine is running. When the engine speeds up, you found a vacuum leak. You could try that. It can be very dangerous. If you hhave a bad plug wite that is arcing to the block, you might cause a fire. Common sense should keep you safe.



Before you start replacing O2 sensors, be advised, they are not cheap. Rockauto has them for about $50.00/each. That is about $150.00 for all three. Replacing working O2 sensors is a waste of money.



You need to make sure there is not a vacuum leak anywhere.





Tom

 

[Steve Hobson]

Thanks to this site I was able to fix this same problem as pictured above. I went to Advanced Auto Parts and bought: “CURVED RADIATOR HOSE” part number (A)70001CS. It fit perfectly with absolutely no modifications at all and cost less than $5.00. My Trac is running better than ever. Be sure to buy the part first as your Trac won’t run without it. This can be done without tools however I had to use a utility knife to cut away the old hose. Also, because I have big hands then I removed the dust cover to allow me a little more room to work . Still, the whole process took less than 10 minutes not including travel time to the parts store.

 

[Fred]

:lol: I thought I was freaking out! I thought, "Didn't I just read that reply to an old post?" :lol:

Thanks for the part # Steve.